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RECLAIM and ICOADS. Scott Woodruff 1 , Philip Brohan 2 , Eric Freeman 3 , Elizabeth Kent 4 , Sandy Lubker 1 , Clive Wilkinson 5 , and Steve Worley 6 1) NOAA Earth System Research Laboratory, USA 2) Met Office Hadley Centre, UK 3) Sourcecorp and CDMP/NCDC, USA
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RECLAIM and ICOADS Scott Woodruff1, Philip Brohan2, Eric Freeman3, Elizabeth Kent4, Sandy Lubker1, Clive Wilkinson5, and Steve Worley61) NOAA Earth System Research Laboratory, USA 2) Met Office Hadley Centre, UK 3) Sourcecorp and CDMP/NCDC, USA 4) National Oceanography Centre, Southampton, UK 5) CDMP/NCDC, USA; & CRU/Univ. of East Anglia, UK 6) National Center for Atmospheric Research, USA
1) RECLAIM • RECovery of Logbooks And International Marine data project • Initiated in 2004, building on EU-funded CLIWOC (1750-1850) project (ES, NL, UK, and some FR) • Website: http://icoads.noaa.gov/reclaim/ • populated with imaged US and UK publications • detailed UK data inventories, etc.
Recent Accomplishments • Imaging by KNMI in 2006 of C19th Dutch logbooks; planned for future digitization by CDMP • Jointly funded UK & CDMP effort to image (268K pp) and digitize (1.5M obs) selected UK Royal Navy (RN) Ship’s Logs for data sparse period (1938-47) ~WW II
Ongoing and Planned UK ProjectsTogether with ACRE, The UK National Archives (TNA), other partners • English East India Co. Logbooks (>1K; 1790-1834) at British Library; many recorded SLP and AT • RN Ship’s Logs from ~WW I (1914-23; ~376K days of obs) • H.O. “Remarks Books” (6K, 1800-1909), Met. Registers (1850-), early balloon data from ships, publications, etc. • Many more logbooks (1669-) untapped at TNA and elsewhere
2) ICOADS • International Comprehensive Ocean-Atmosphere Data Set • Original COADS project initiated in 1981 • Joint in US between NOAA (ESRL and NCDC) & NCAR • Plus extensive international contributions such as: • DWD, JMA, KNMI, UK Met Office and National Oceanography Center, Southampton • Website including data and metadata access: http://icoads.noaa.gov/ • Formal links to JCOMM under consideration
Major update in progress:Release 2.5 (~1662-2000) • 1662-1949 processed (red) – 1950-69 being checked • 1970-2000 (approx.) by late 2008 Green spans periods of new sources for R2.5 R2.0
R2.5 (bars): increases in data density: 1800-1969 UK MDB UK RN Japan Kobe US MMJ R2.0
R1 1985 R2.0 2002 Evolving national (+ HSST) data mix HSST data (abbrev. fmt.) R2.5 2008 Thompson et al. 2008, Nature: A large discontinuity in the mid-C20th in observed global-mean surface temp
R2.5: Decadal changes in spatial density; focus on 1930s(red= + , grey= 0 , blue= –) Dutch deck 193: empty box (data never received?) UK MDB deck 215 (German data): additional previously undetected dups removed, or replacement by better quality data from DWD HSST deck 156: Previously undetected dups w/ deck 193 (due to reversed sign of gravity correction in HSST) removed – but no fix available for empty box
Future Directions:a) Update Frequency • Aim for monthly extensions • GTS plus some delayed-mode (DM) data • replace NCEP Real-time data • Challenges: • NOAA funding pressures – larger role for NCDC • Historical (CDR) updates not suitable for “operations” • VOS call sign masking • Stemming from security and commercial concerns • NCEP GTS Dec 2007: all ships masked • Mandated WMO BUFR transition • could be disruptive to data quality and continuity
GTS DM buoy data WMO Pub. 47 metadata DM ship/buoy/oceanographic data through 1997/1997/1996 > GTS drifter reports consolidated in DM Recent data mixture complexity: platform types;plus DM v. GTS data Potential for artificial signals from DM vs. GTS data mixture changes R2.5
Future Directions:b) Improve Data Quality Control • Existing ICOADS QC • Out-of-date algorithms and QC limits • Can be insufficiently responsive to genuine climate signals (“trimming” problem) • Improvements could be tied into: • Enhanced internationalization (JCOMM): • E.g., improved VOS data flow: TT-DMVOS • Proposed “Climate ICOADS” Project • For bias-adjusted/valued-added products
R2.5 ad hoc QC improvement: Trimming limits (July) for RH: Used 1910-49 for pre-1910 data(End years of the three original trimming data periods (1854-1909, 1910-49, and 1950-79) shown) QC gaps in other variables e.g. SLP and SST
c) Future Directions:Additional Data (Metadata) Rescue & Blending Green =digitized Yellow=partially Red =undigitized • But costly format translations w/ careful validation required: • International Maritime Met. Archive (IMMA) format: has extensibility & flexibility to preserve original data
Conclusions • Much useful RECLAIM & ICOADS work remains, e.g.: • HSST replacement desirable (as feasible; e.g., Dutch not?) • negotiate exchange of more DWD historical marine archive • improve SST indicator information (e.g., 1969-73 US data) • IMMA observations: critical foundation for all later work • intensive translation validations costly, but often worthwhile • pre-evaluation of data quality of newly available sources? • possible role for additional international cooperation (e.g., UK) • CLIMAR-III (6-9 May, Gdynia, Poland) • 3rd JCOMM Workshop on Advances in Marine Climatology • summary being finalized; WMO Bulletin article planned • recommendations relevant to RECLAIM, ICOADS, and ACRE